PHY101 Assignment 5: (Spring 2011) Solution

[chowder]

 

Q # 1

 

Measuring wavelengths with a CD, A LASER beam of wavelength λ = 632.8nm shines at normal incidence on the reflective side of a compact disc. The track of tiny pits in which information is coded onto the CD are 1.60μm apart. For what angles of reflection (measured fro m normal) will the intensity of light be maximum?                     Marks = 7

 

Q # 2

 

The plate on the back of a certain computer scanner says that the unit draws 0.34A of current from a 120V, 60Hz line. Find (a) the root mean square current (b) the current amplitude (c) the average current (d) the average square current. 

 

Q # 3

 

Give several examples of electromagnetic waves that are encountered in everyday life. How are they all alike? How do they differ?                                                       Marks = 5

 

[chowder]

 

question 2 answer :

given  that

  current  drqwn by a computer scanner  I = 0.340A

  voltage  = V = 120v

 frequency  f = 60Hz

 

  power  in the scanner  P = VI

                                      = 40.8W

 resistance  in the   scanner  R = V/I = 352.9Ω

 a) root mean  square  current  I_rms = √P/R

                                                      = 0.34A

 b) max  current  I _max = I_rms * √2 = 0.480A

 c) average current  I_avg = 0.6366 * I_max  = 0.3055A

 d) average  square  current  = ( I_rms)²  = 0.1156A

Question 3 answer(From yahoo Answer)

--Gamma rays are emitted by thallium nuclei during stress tests for heart disease.
--X-rays are used to image body interior parts either in "photos" or CT scans.
--Ultraviolet light from the sun or tanning lamps has cosmetic effects.
--Visible light illuminates dark nights or rooms. It also exposes films for photography.
--Infrared light is used by some stoves for cooking. Infrared lamps keep hot food warm.
--Microwave radiation also cooks food or boils water.
--Radar waves are used by airplane pilots, ground observers, and ship and boat crews to image solid objects in fog or darkness.
--Radiofrequency radiation interacts with strong magnetic fields to view interior body parts by magnetic resonance imaging. Lower energy radio waves propogate radio and TV signals

[cancerian]

where is the answer of question no. 1

 

[chowder]

wo tu urrr gya ..  wo mujay nae ayta  hira ko bolo us ko buht achi ayti hai physics ..

[Amber Hashmi]

 

A.O.A

             please some one share question no 1 of  5th assignment .......

             If any one know about this plz share.

[Muhammad_Mansoor_Waqas]

theta = 27 degree

[Amber Hashmi]

 

 

    pls share 1st que solution here

[Amber Hashmi]

 

 

    pls share 1st que solution here

[cancerian]

hira please help me in question no. 1

[kasu]

All the questions which are solved here totally wrong.